bugfix: when syslog was enabled in the "error_log" directive for nginx 1.7.1+, use of init_worker_by_lua or ngx.timer.at() would lead to segmentation faults. thanks shun.zhang for the report in #426.

src/ngx_http_lua_initworkerby.c

@@ -224,11 +224,21 @@ ngx_http_lua_init_worker(ngx_cycle_t *cycle)
     r->loc_conf = http_ctx.loc_conf;
 
     clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
+
+#if defined(nginx_version) && nginx_version >= 1003014
+
+    ngx_http_set_connection_log(r->connection, clcf->error_log);
+
+#else
+
     c->log->file = clcf->error_log->file;
+
     if (!(c->log->log_level & NGX_LOG_DEBUG_CONNECTION)) {
         c->log->log_level = clcf->error_log->log_level;
     }
 
+#endif
+
     if (top_clcf->resolver) {
         clcf->resolver = top_clcf->resolver;
     }

src/ngx_http_lua_timer.c

@@ -295,11 +295,21 @@ ngx_http_lua_timer_handler(ngx_event_t *ev)
     r->loc_conf = tctx.loc_conf;
 
     clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
+
+#if defined(nginx_version) && nginx_version >= 1003014
+
+    ngx_http_set_connection_log(r->connection, clcf->error_log);
+
+#else
+
     c->log->file = clcf->error_log->file;
+
     if (!(c->log->log_level & NGX_LOG_DEBUG_CONNECTION)) {
         c->log->log_level = clcf->error_log->log_level;
     }
 
+#endif
+
     dd("lmcf: %p", lmcf);
 
     ctx = ngx_http_lua_create_ctx(r);

t/106-timer.t

@@ -13,7 +13,7 @@ our $StapScript = $t::StapThread::StapScript;
 
 repeat_each(2);
 
-plan tests => repeat_each() * (blocks() * 8 + 76);
+plan tests => repeat_each() * (blocks() * 8 + 72);
 
 #no_diff();
 no_long_string();
@@ -2162,3 +2162,33 @@ qr/\[lua\] content_by_lua:\d+: elapsed: .*?, context: ngx\.timer/,
 "lua release ngx.ctx at ref ",
 ]
 
+
+
+=== TEST 32: syslog error log
+--- http_config
+    #error_log syslog:server=127.0.0.1:12345 error;
+--- config
+    location /t {
+        content_by_lua '
+            local function f()
+                ngx.log(ngx.ERR, "Bad bad bad")
+            end
+            ngx.timer.at(0, f)
+            ngx.sleep(0.001)
+            ngx.say("ok")
+        ';
+    }
+--- log_level: error
+--- error_log_file: syslog:server=127.0.0.1:12345
+--- udp_listen: 12345
+--- udp_query eval: qr/Bad bad bad/
+--- udp_reply: hello
+--- wait: 0.1
+--- request
+    GET /t
+--- response_body
+ok
+--- error_log
+Bad bad bad
+--- skip_nginx: 4: < 1.7.1
+

t/124-init-worker.t

@@ -706,3 +706,37 @@ ok
 [alert]
 [emerg]
 
+
+
+=== TEST 18: syslog error log
+--- http_config
+    #error_log syslog:server=127.0.0.1:12345 error;
+    init_worker_by_lua '
+        done = false
+        os.execute("sleep 0.1")
+        ngx.log(ngx.ERR, "Bad bad bad")
+        done = true
+    ';
+--- config
+    location /t {
+        content_by_lua '
+            while not done do
+                ngx.sleep(0.001)
+            end
+            ngx.say("ok")
+        ';
+    }
+--- log_level: error
+--- error_log_file: syslog:server=127.0.0.1:12345
+--- udp_listen: 12345
+--- udp_query eval: qr/Bad bad bad/
+--- udp_reply: hello
+--- wait: 0.1
+--- request
+    GET /t
+--- response_body
+ok
+--- error_log
+Bad bad bad
+--- skip_nginx: 4: < 1.7.1
+